1. Field of the Invention
The present invention generally relates to a portable, adjustable, multipurpose activity surface. More specifically, it relates to such an activity surface adapted for use on a person""s lap or on any relatively flat or stable surface.
2. Discussion of the Related Art
There are currently several devices available for performing activities on an individual""s lap or at a computer station. However, such devices suffer from limitations of size and ease of use, because they are not adaptable to a wide variety of different individual preferences and ergonomic positions.
For example, most current devices are intended for single or limited uses, such as for the manipulation of a computer mouse and similar small objects (see U.S. Pat. No. 6,062,522). Thus, such devices are unworkable for a broad scope of activities. Some other available devices are commonly referred to as lap trays. However, devices such as these are either non-adjustable (see U.S. Pat. No. 6,050,200) or they are cumbersome, having legs and the like (see U.S. Pat. No. 6,044,758). Still other lap trays have recesses and pockets for holding objects such as food and drink (see U.S. Pat. No. 5,915,561). Although the use of straps is one attempt to solve the problem of adapting the tray to a wide variety of uses and individual preferences, such straps are often uncomfortable and somewhat restraining for the individual. One attempt to solve the problem of adapting the tray to the legs of an individual is to use a contoured area on the bottom for receiving the legs of the user (see U.S. Pat. No. 6,003,446). However it is still desirable to have a bottom that is adaptable to an individual""s legs as well as a wide variety of other surfaces.
Several devices are also heavy, being constructed of wood, or are cumbersome, having compartments, housings, receptacles, projections, legs or handles which make them time-consuming to set up, generally inconvenient to use or adjust, and difficult to quickly put aside. Still other devices are configured with strapping or belting (see U.S. Pat. No. 5,862,933), which are confining to use, and otherwise restrict body positions.
Yet other devices are complicated in design with rigid movable parts requiring either screws, hinges, hooks, brackets, slots or other attaching or enabling mechanisms, making them costly to design, manufacture and build. This expense is then passed on to the consumer in higher retail prices. Some devices have legs or vertical supporting members that restrict the device""s use by requiring a conforming support for the legs or vertical supporting members. Since they are mostly designed to rest adjacent to and outside the thighs, they also prevent the user""s legs from naturally splaying in a comfortable position.
Most devices are also devoid of sufficient padding between the lap and the bottom of the device, making them uncomfortable to use when placed on the lap, especially for long periods of time. In addition, the devices currently available are limited in their ergonomic utility, requiring the user to adjust to the device""s orientation rather than being able to fully adjust the device to serve the intended use whatever the user""s body position. That is, the devices are designed to usually rest on or above the lap. But the lap itself may be up-sloping or down-sloping, depending on the physiology or posture of the user. The result is the activity surface is in the same front-to-back orientation, sloping upward or downward. This most often is not the ideal configuration for performing the intended activity and usually results in an inappropriate adaptation of the body. Those devices with legs or vertical supporting members are subject to the geometry of that upon which the user is seated and can pose even more ergonomic problems. Moreover, many of the devices arguably create or exacerbate the ergonomic anomalies they intend to alleviate. Thus, the user is required to negotiate lips, ridges and other contours that can form pressure points between the device and the user""s upper extremities or require the user""s upper extremities to be used while not adequately supported.
Thus, there exists a need for a portable activity surface that is adjustable to accommodate various user physiologies and postures and at the same time is comfortable and adaptable to a variety of purposes or tasks. Ideally the device will be adapted for use on a person""s lap and will be adjustable through a wide variety of positions while large enough to accommodate a wide range of different activities and users. The present invention satisfies these needs and provides related advantages as well.
The present invention provides an adjustable activity surface having a support pad of a generally triangular or wedge configuration that has a resting surface, a forward surface, a rearward surface and a sloping surface. The activity surface also has a platform adapted to removeably mount on the sloping surface. The height of the platform can be increased by moving the platform up the sloping surface. The height of the platform also can be decreased by moving the platform down the sloping surface, thereby providing adjustment of the platform to accommodate individual physical sizes and preferences.
The present invention also provides an adjustable activity surface where the support pad has a resting surface, a forward surface and a sloping surface. There is a platform adapted to contact and be supported on the sloping surface and its height can be increased by moving the platform up the sloping surface, or its height can be decreased by moving the platform down the sloping surface.
In additional embodiments, the support pad and the platform are held in contact by friction or hook-and-loop fastening means. The activity surface can also have attachment means for securing objects to the platform. The attachment means can be elastic or rubber bands, nylon rope or leather belts. There can also be a lap belt or lap strap securing the device to the user""s lap. In additional embodiments, the platform can be made of a magnetic material, or it can be a dry erase white board.
The invention also provides methods for making and using the activity surface by taking a support pad having a resting surface, a forward surface, a rearward surface and a sloping surface; contacting a platform with the sloping surface; placing the activity surface on an individual""s lap; removing the platform from the sloping surface of the support pad; moving the support pad either toward or away from the individual; and repositioning the platform on the sloping surface of the support pad, wherein an activity surface is provided that can be adjusted to a position that accommodates the size and preference of the individual.